Pre cook the pasta shells. (I suggest cooking 15 even though you will only fill 10 just in case a few shells rip!) If using your Instant Pot to pre cook the shells, cover the shells with water and cook on Manual HIGH for 3 min with a 5 min NPR. If using the stove top, boil the shells until al dente.
Rinse the shells under cold water when they are finished cooking.
While the shells are boiling, make the cheese filling.
Combine the cottage cheese, 1 cup of parmesan cheese, shredded chicken, parsley, salt, pepper and the egg in a medium sized bowl. Stir thoroughly.
Preheat the oven to 350°.
Pour 1/2 cup of the Alfredo sauce on the bottom of an 8×8 pan.
Spoon the filling into each shell, one at a time, arranging the shells in the pan as you go. You will end up with 2 rows of 5 shells.
Pour the remaining Alfredo sauce on top of the shells. Top with the remaining 1/2 cup of parmesan cheese.
Bake at 350° for 30 minutes.
Allow the shells to cool for 5-10 minutes before serving.